Epidermal cysts of periorbit and intraorbit are common problems to ophthalmologists, but giant periorbital epidermal cyst is exceedingly rare. Only a few cases have been reported previously. A 62-year-old woman presented with a large right periorbital area mass that resulted in right upper lid complete ptosis and severe gaze limitation in all directions. Visual acuity of right eye was finger count (20/2000). Computed tomography and magnetic resonance imaging revealed a bone-destroying mass involving the lateral side of the right superior orbital limb. Complete surgical removal was performed through skin incision. The superior-lateral orbital limb was reconstructed with bone cement and Leibinger plate. Pathologic examination revealed a giant epidermal cyst (9.8×5.2×4.0 cm) of the periorbital area. After surgery, there was near-complete resolution of ptosis and gaze limitation. In addition, marked elevation of visual acuity was observed (20/125 on best-corrected visual acuity).